As a result of the 9/11 WTC attack, how many children were killed? Where is this documented?

Answer 1

Interesting question. The following web-site has every statistic possible except for the number of children killed. I am thinking the majority of children killed were on the four airplanes that crashed as a result of the attacks. The only statistic this web-site provides related to children is:
Estimated number of children who lost a parent: 3,051

http://nymag.com/news/articles/wtc/1year/numbers.htm

Answer 2

I only recall one child being killed. You can go back into the records of the NY Times (online or at the library). They published profiles of every victim, a few a day, for weeks after 9/11.